Transmission System Reliability Assessment Considering Multiple Circuits Transmission Lines Which Have Common Right-of-Way

With environmental and financial constraints, multiple circuits transmission lines which have common right-of-way (MCTLCW) or common structure are more widely used in the electrical grid. So it is necessary to investigate the reliability of these structures on the composite power system. In this paper, three different contingency modes are considered, which are line independent fault, dependent fault and common mode fault. The multi-state model for the circuits with common right-of-way is first calculated using the analytical methods. Then the Monte Carlo simulation is utilized to perform reliability assessment for the bulk power system. A practical system is investigated by the proposed model and method. The results verify the correctness and effectiveness of the proposed method and the impacts of the circuits with common right-of-way on the reliability indices are discussed.